AAT1171
600mA Voltage-Scaling Step-Down Converter
for RF Power Amplifiers with Bypass Switch
Typical Characteristics
Light Load Switching Waveform
(PWM Mode; VIN = 4.2V; VOUT = 0.6V; RL = 10Ω;
Light Load Switching Waveform
(LL Mode; VIN = 4.2V; VOUT = 0.6V; RL = 10Ω;
COUT = 4.7µF; L = 2.2µH)
C
OUT = 4.7µF; L = 2.2µH)
VOUT
(AC coupled)
20mV/div
VOUT
(AC coupled)
20mV/div
IL
100mA/div
IL
200mA/div
0
0
VLX
2V/div
VLX
2V/div
0
0
Time (200ns/div)
Time (1µs/div)
DAC Transient Response in PWM Mode
(VIN = 3.6V; RL = 10Ω; COUT = 4.7µF; L = 2.2µH)
DAC Transient Response in LL Mode
(VIN = 3.6V; RL = 10Ω; COUT = 4.7µF; L = 2.2µH)
VOUT
1V/div
VOUT
1V/div
3.3V
3.3V
0.6V
1.2V
0.6V
0
0
1.2V
VDAC
0.5V/div
0
VDAC
0.5V/div
0
0.2V
0.2V
Time (25µs/div)
Time (25µs/div)
Bypass Transient Response
(PWM Mode; VIN = 3.6V; RL = 10Ω; COUT = 4.7µF; L = 2.2µH)
Bypass Transient Response
(LL Mode; VIN = 3.6V; RL = 10Ω; COUT = 4.7µF; L = 2.2µH)
3.5V
3.5V
VOUT
1V/div
VOUT
1V/div
0.6V
0.6V
0
0
VBYP
1V/div
0
VBYP
1V/div
0
Time (25µs/div)
Time (25µs/div)
10
1171.2006.06.1.0
ANALOGICTECH [ ADVANCED ANALOGIC TECHNOLOGIES ]
